[Abstract] Successful Combined Liver and Kidney Transplant with Positive Flow Crossmatch and Multiple High Donor Specific Antibody Levels: 1270

Introduction: Liver transplantation prior to positive crossmatch kidney transplantation is known to protect the kidney allograft against hyperacute rejection. Immunomodulation therapy and staggered transplantation of organs allowing time for the liver to „absorb“ the antibodies prior to implantation of the renal allograft, are the most common practices. Methods: A 60 year-old Caucasian female with a history of NASH cirrhosis (MELD score 30) and diabetic nephropathy underwent combined liver and kidney transplant. The kidney transplant was performed 10 hours after a successful liver transplant. The kidney allograft began functioning soon after reperfusion. She received basiliximab 20 mg I.V. and methylprednisolone 500 mg I.V. during the anhepatic phase of the liver transplant procedure and mycophenolate mofetil 1000 mg I.V. before reperfusion of the kidney allograft. Maintenance immunosuppression consisted of prednisone, mycophenolate mofetil, and tacrolimus. Results: T and B-cell flow crossmatches were positive before liver and kidney transplants, 3, 7 and 9 hours after liver transplant. Both T and B-cell flow crossmatches were negative at 20 weeks post-transplant and currently remain negative (Figure 1). Multiple high levels of Donor Specific Antibodies (DSA) to HLA Class I and Class II were identified pre- and post-transplant. The highest pre-kidney MFI was for A1 (>10000) and DQ2 (3908). All DSA remained positive at day 1 post-transplant. However, four specificities (B8, DR17, DQ6, and DR52) dropped below 1000 MFI by post-op day 4. DSA to A33, B71, and DQ2 were not present at day 14 and have not reappeared. DSA to A1 (1408) and DR52 (1894) remain present at 15 months (Figure 2). Liver and kidney allografts are functioning very well 15 months post-transplant. She has not developed any episode of acute cellular or antibody mediated rejection to date. Conclusion: Positive flow crossmatch and high levels of DSA are not a contraindication for a combined liver and kidney transplant. We suggest that in highly sensitized patients who undergo kidney transplant after a successful liver transplant, treatments such as plasmapheresis, polyclonal antibody depleting or B-cell receptor blocking therapies may not be necessary to prevent hyperacute or acute antibody mediated or cellular rejection.